New Gardening to Do!

Plant Profiles

The Best Season Ever: Chestnut Rose in Bloom

Chestnut rose is unique: Out of all the roses hardier than Zone 7, it alone becomes so large and woody that any one of its stems could be trained as a trunk, and that stem's branches the trunk's canopy. In other words, this is a "tree" rose can become a true tree.

The trunk is as thick as my forearm...

..but the canopy it has produced is so large that the trunk seems toothpick thin.

Yes, you can prune chestnut rose to control size, and thank goodness you can; very old specimens can be twelve feet or more tall and wide. I have the room for my rose tree (technically, it's an enormous standard) to grow as large as it wants. The wood of Rosa roxburghii f. normalis must be unusually strong. Some years ago, I released the trunk from the ropes that had guyed it a bit closer to the rusted-iron stake at its left. Since then, neither blizzards, ice, nor high winds have brought about any damage or instability. Not so much as a twig has ever snapped, let alone a major limb.

Chestnut rose produces large pink flowers with a single circle of five petals.

The buds and young flowers are a bit darker but, by the time the blossoms have matured, their petals are nearly white at the base. Truth to tell, I'd love to know of a white-flowered form but, alas, the only other available forms also have pink petals.

Few of the flowers on my chestnut rose ever mature to the large, brown, fuzzy-capped hips that, indeed, resemble chestnuts. Rosa roxburghii is native to China, so perhaps what's needed is an Asian pollinator not present here in eastern North America.

Roses are self-fertile, so I don't need a second chestnut rose for cross pollination but, in another life, I'd have sited two chestnut roses in one of my pair of pink borders. The borders face each other across an eight-foot alley of grass, and I'd have planted a chestnut rose on each side so the two could greet each other—and, perhaps, enhance the "chestnuttiness" of each.

But, as I say, that's a pairing for another life. For this one, my solo Rosa roxburghii will remain planted in one of the streetside beds, and my pink borders (already stuffed, anyway) will get along without it. In the spirit of public service as well as one-upsmanship, siting this giant standard of chestnut rose in full view will tantalize but also puzzle most people with a fondness for traditional tree roses. They are formed by grafting a trunk onto a rootstock, and a canopy of a yet a third form of rose atop the trunk. Such tree roses aren't usually hardy north of Philadelphia. But there's my tree rose, many times larger than those others, and perfectly hardy right here in southern New England.

Now the secret is out.

Here's how to grow this extraordinary species—whose limbs are the most massive of any rose that can be grown in-ground north of Florida—as well as a detailed look at its striking bare branches in winter.